The casting is made out of styrofoam. thats all
Yeah, I know, it is just crazy how it makes the head look like it is styrofoam too. I am a little confused though, how do they get styrofoam to hold molten aluminum or steel without melting? Obviously I know nothing about casting parts.
-da chinchilla
<img src="http://registry.gmenthusiast.com/images/jiggamon/avatar15569_2.gif">
2.4 CavaWeir (a.k.a. jiggamon) wrote:Definitely take the valves out. You will hit them with the sanding wheels when you port it. Porting is not just about making things bigger, it is about cleaning up the casting flash, and smoothing sharp radius edges...all things which are huge hindrances to airflow. So even if the intake ports match the gasket already, you should still go in and break all the sharp edges. And definitely polish the combustion chamber as well. It increases airflow and keeps carbon from sticking to have the chamber and the exhaust ports polished.
By the way, is that head make of styrofoam? 
Anyone know where I can get info on polishing the exhaust side? I have a dremmel, will that be good enough, if i get the right polish. also, should i use a finner grinder first, because as you can see in the pic, its not smooth.
Also, for the intake side, what bit should I use to do that side? standard abrasive kit? i remember that from my p&p research a few months ago, but will a dremmel be good enough to do it?
2.4 CavaWeir (a.k.a. jiggamon) wrote:http://www.sa-motorsports.com/diyport.shtm
That should give you a good method.
ya, i've read that already, a few months ago. I think I'll just plan to go to lowes this evening, and get the polish, and some attachments for my dremmel.
I felt inside the intake, and i definately felt a few spots that could be smoothed; things from casting.
The polishing wheels in the SA kit are great. Get the ones for small engines (like lawnmowers), they fit in smaller areas better and will polish everything. Be sure you use WD-40 to do the polishing.
Nice site nova
-da chinchilla
<img src="http://registry.gmenthusiast.com/images/jiggamon/avatar15569_2.gif">
2.4 CavaWeir (a.k.a. jiggamon) wrote:The polishing wheels in the SA kit are great. Get the ones for small engines (like lawnmowers), they fit in smaller areas better and will polish everything. Be sure you use WD-40 to do the polishing.
Nice site nova
I went ahead anf got the one recommended in the site above.
http://store.summitracing.com/default.asp?target=partdetail.asp?part=SAI-260001
What do you mean by use wd-40 for the polishing. spary it in while polishing? does that help to polish the metal?
I had trouble fitting the cross-buffs into the ports of the head, so I got the small engine porting kit for some extra wheels and the smaller cross buffs. It was part # SAI-260007. You can just get the smaller cross-buffs separately.
Spray the cross buff with WD-40 and wet the walls of the port as well. This will keep the cross buff from wearing down as fast and will polish up the walls like a mirror.
-da chinchilla
<img src="http://registry.gmenthusiast.com/images/jiggamon/avatar15569_2.gif">
Why would you go through all of that work to leave the chambers prettymuch stock? Looks good but for god sakes polish the chambers and work around the valves alittle to unshroud them abit. keep up the good work.
_______________________
** Flat Broke Racing Inc.**
Manitoba Motorsports wrote:Why would you go through all of that work to leave the chambers prettymuch stock? Looks good but for god sakes polish the chambers and work around the valves alittle to unshroud them abit. keep up the good work.
I am going to polish the cambers, and the cambers have already been de-shrouded near the edges.
2.4 CavaWeir (a.k.a. jiggamon) wrote:I had trouble fitting the cross-buffs into the ports of the head, so I got the small engine porting kit for some extra wheels and the smaller cross buffs. It was part # SAI-260007. You can just get the smaller cross-buffs separately.
Thanks for the insight.
And thanks to everyone for the input, and helping me out to make this a great cylinder head.
hey jeff its lookin good
nice to see your car is comin along after I got YOUR valves in the mail instead of mine!
keep us updated on the progress man
I polished the exhaust ports, and they look nice and shinny. Thanks for that tip on wd-40. seems to work well. I have started on the intake side, and been getting the casting problem out of the way, i think thats all i'll do, because its pretty port matched already. I'll try and have some pics up tonight, if i'm not too busy.
I'm glad the exhaust polishing went well. Remember not to polish the intake side, just run it with 120grit cartridge rolls ...no finer than that.
Then polish the chambers as well.
I'll be waiting for the pics.
-da chinchilla
<img src="http://registry.gmenthusiast.com/images/jiggamon/avatar15569_2.gif">
2.4 CavaWeir (a.k.a. jiggamon) wrote:I'm glad the exhaust polishing went well. Remember not to polish the intake side, just run it with 120grit cartridge rolls ...no finer than that.
Then polish the chambers as well.
I'll be waiting for the pics.
why wouldnt you pnp the intake side??
the polishing is to keep the carbon from sticking and building and also to keep pre-ignition and detonation from occurring in the chamber. The intake ports should be rough to the touch to give the air and fuel vapor a mixing motion as they flow through the ports.
Oh and I was wrong earlier, I said not finer than 120 grit, but I meant to say 80 grit. Use the 40 grit to smooth out any rough spots and around the valve guides, and then finish it with 80 grit to leave it feeling rough to the touch.
-da chinchilla
<img src="http://registry.gmenthusiast.com/images/jiggamon/avatar15569_2.gif">
ok that makes since...
so you can port them but dont polish(much)...?
right, port, but no polish on intake, polish chamber, and port and polish exhaust. The most benefit the head will receive is the exhaust side, so be sure to really port and polish it well.
-da chinchilla
<img src="http://registry.gmenthusiast.com/images/jiggamon/avatar15569_2.gif">
yea i saw how small they are when i installed my header..... my dad was rofl(bastard!)...
anyways thanks for the info...
Images are back!
side angled view, it was hard to show their true shinnyness
again, exhaust side:
Better Angle:
Intake valve:
Another valve
Intake runner
Another view
I'm stilling finishing the side where the valve is, on most of the cylinders.
Sorry for the newb question but what are you guys referring to in the bottom quote? Are you talking about a lip that is around the exhaust port where the manifold flange mates to it?
I would like to know as Im trying to figure all this out,
VTLoki keep up the good work and thanks for posting pics,
-Erik
Quote:
Also noteworthy was that the porter took out the vanes from your exhaust runners. I guess seeing as you plan a turbo build that should be OK, but from what I understood those should remain in everything other than an all out racing build...
he's talking about this nub type thing in the top of this picture. I'm not 100% sure what it does, nit i think of it like a shark fin, and it keeps the air straight when it comes out, maybe improving velocity? can anyone else describe it better?
